Access Type

Open Access Dissertation

Date of Award

January 2015

Degree Type


Degree Name



Communication Sciences and Disorders

First Advisor

Li Hsieh

Second Advisor

Joseph Murray


Purpose: To determine if the severity of dysphagia, as determine by Penetration Aspiration Scale (PAS) ratings and pharyngeal residue scale ratings in individuals with ALS, can be predicted through performance on diadochokinesis (DDK) and force vital capacity (FVC) measures.

This study was designed to evaluate differences in performance of clinical measures and objective swallowing severity ratings between individuals with ALS and a Control group of similar age. The goal of this study was to attempt to develop a clinical assessment battery that can predict swallowing impairment in ALS patients. In addition, potential predictive relationships between dysphagia ratings and other commonly utilized measures in the evaluation and treatment of ALS including duration of disease, type of onset (axial, bulbar, mixed), current Amyotrophic Lateral Sclerosis Function Rating Score - Revised (ALS-FRS-R) score, body mass index, and the Dysphagia Handicap Index (DHI) patient-reported outcome based dysphagia tool were also investigated.

Swallowing function was assessed with three thin liquid boluses of increased volume, two 5mL pudding boluses and one piece of graham cracker. Pharyngeal residue, PAS and number of swallows per bolus was rated by two independent investigators. Between-group findings included significant impairment in function in the ALS group on all clinical measures and all swallowing severity ratings with the exception of the smallest liquid bolus trial, compared to the performance of the control group. Within the ALS group, significant correlations were present to support the hypothesis that swallowing function can be predicted by various clinical measures including DDK, FVC the DHI and number of swallows per bolus. Duration of disease and type of onset were significantly correlated with severity of dysphagia in ALS.

In conclusion, clinical measures can be beneficial in predicting severity of dysphagia in individuals with ALS. There is a significant correlation between DDK, FVC, DHI, number of swallows per bolus with decline in swallowing function in ALS.